Two-Tier Client/Server

A two-tier client/server works when most or all of the application logic and data is hosted on a server. The client integrates with the presentation layer and accesses the server for application specific tasks and processing.

For example, the core application and data are installed at a central server. One or more client devices uses its client-end application to request data or processes from the server. The server sends the required data or performs a process to fulfill the query. In another two-tier client/server instance, such as a data backup architecture, the application access and logic may be with the client device, whereas the server stores and provides the core data.